An excellent example of how macros should be adjusted based on the overall body composition and sports performance desired from the diet. Many seem to claim that even the MFP standard macros will all but allow you to wither and die from lacking protein. Surely these elite distance runners somehow do this without muscle mass?

If the left is one's goal more than the right, it is one's body to do with as they wish.

The type of training one does has a far greater impact on their physique then their macros. All the protein in the world will not build muscle if one does not lift...

Well of course, but it isn't an either-or problem. I don't have to choose between training like a marathon with a sprinter's macros, or a sprinter with a marathoner's macros. I can choose to have a sprinter's macros and training if that reflects the composition I'm looking for. If I am looking to retain muscle mass, I'm probably better off having macros similar to someone who has more muscle mass, regardless of my specific training.

I agree the macros are important, I just think they are overemphasized...

An excellent example of how macros should be adjusted based on the overall body composition and sports performance desired from the diet. Many seem to claim that even the MFP standard macros will all but allow you to wither and die from lacking protein. Surely these elite distance runners somehow do this without muscle mass?

If the left is one's goal more than the right, it is one's body to do with as they wish.

The type of training one does has a far greater impact on their physique then their macros. All the protein in the world will not build muscle if one does not lift...

Well of course, but it isn't an either-or problem. I don't have to choose between training like a marathon with a sprinter's macros, or a sprinter with a marathoner's macros. I can choose to have a sprinter's macros and training if that reflects the composition I'm looking for. If I am looking to retain muscle mass, I'm probably better off having macros similar to someone who has more muscle mass, regardless of my specific training.

I agree the macros are important, I just think they are overemphasized...

Well I'd agree they aren't going to replace actual exercise in terms of composition and performance goals. I'd definitely agree that the marathoner's build has at least 75% to 95% to do with the exercise he's doing.

In the case of the marathoners shown, very low protein levels, in a 600 calorie a day deficit during training, yet retaining the muscles that are trained through the deficit, and used for their particular sports.

There are studies on VLCDs, and even with very low intake, people that have the training levels up retain the majority of the trained muscle. I'd bet the Kenyans worry more about running and less about the perfect macro ratios myself.

Macros to fit the training make complete sense. Those choosing macros in hopes that it eliminates the need for hard training... well good luck with that. I'd venture to say that for many people, there is a lot of wiggle room in macro ratios that they wouldn't even notice.

In the case of the marathoners shown, very low protein levels, in a 600 calorie a day deficit during training, yet retaining the muscles that are trained through the deficit, and used for their particular sports.

How are they at very low protein levels given actual calories consumed?

80% to 90% carbs, 5% to 12% protein, 5% to 8% fat. I achieve that easily without thinking by eating whole-plants food and avoiding animal products altogether. weight loss comes automatically on the long term and it is maintainable and sustainable long term as well.

if OP wants to preserve muscle mass than getting 12% protein is a horrible idea...

and avoiding animal foods has nothing to do with this topic...

I gained muscle mass and lost fat while going on a 60-30-10 Carb:Fat:protein plant based diet. Even our mother's milk is only like 7% protein meaning the fitness industry has fed us BS that protein is the most important macronutrient and we need 40% plus or our muscles won't recover from working out. Don't believe in the hype like I did.

Two studies[3][4] indicated that 12-15% of calories from protein is sufficient for active individuals (60-75g of protein for an individual eating a 2000 calorie diet). While two more recent studies [5][6] argue for higher intake - the first study reports that greater than 1.6-1.8 g/kg of bodyweight (0.7-0.8 g/lb of bodyweight) may be necessary, while the second study indicates that up to 3.0 g/kg of bodyweight (1.4 g/lb of bodyweight) isn't harmful, and may have additional minor benefits.

According to the International Society of Sports Nutrition, protein intakes of 1.4-2.0 g/kg of bodyweight (0.6-0.9g/lb of bodyweight) for physically active individuals is not only safe, but may improve the training adaptations to exercise training. [7]. The American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine also support high protein intake for active individuals[8] in the range of 1.2-1.7 g/kg of bodyweight (0.5-0.8 g/lb of bodyweight).

The reasons for the above tend to be increased leucine oxidation (a marker for amino acids being used for fuel, by being turned into glucose) that requires a higher intake of amino acids to negate and preserve nitrogen balance.[9][7] Additionally, increasing protein intake above the previously defined RDA 'daily allowance' will increase protein synthesis and, at levels higher than double this total, decrease protein breakdown.[10] Increased muscular hypertrophy is seen as beneficial to sports performance.

During Weight Loss

High protein diets have been found to preserve lean body mass when dieting in both obese people[11] and athletes [12] and has also been shown to improve overall body composition[13]. A doubling of protein intake from 0.9g/kg (near the daily recommended intake for the general population) to 1.8g/kg is able to preserve lean muscle mass during short-term and relatively drastic drops in calories.[14]